/* Copyright (c) 2006 Kelvin Luck (kelvin AT kelvinluck DOT com || http://www.kelvinluck.com)
 * Dual licensed under the MIT (http://www.opensource.org/licenses/mit-license.php) 
 * and GPL (http://www.opensource.org/licenses/gpl-license.php) licenses.
 * 
 * See http://kelvinluck.com/assets/jquery/jScrollPane/
 * $Id: jScrollPane.js 2537 2007-07-31 21:52:08Z kelvin.luck $
 */

 jQuery.jScrollPane={active:[]};
jQuery.fn.jScrollPane=function(settings){settings=jQuery.extend({scrollbarWidth:10,scrollbarMargin:5,wheelSpeed:18,showArrows:false,arrowSize:undefined,animateTo:false,dragMinHeight:1,dragMaxHeight:99999},settings);
return this.each(function(){var $this=jQuery(this);
if(jQuery(this).parent().is('.jScrollPaneContainer')){var $c=jQuery(this).parent();
var paneWidth=$c.innerWidth();
var paneHeight=$c.outerHeight();
var trackHeight=paneHeight;
if($c.unmousewheel){$c.unmousewheel()}jQuery('>.jScrollPaneTrack, >.jScrollArrowUp, >.jScrollArrowDown',$c).remove();
$this.css({'top':0})}else{this.originalPadding=$this.css('paddingTop')+' '+$this.css('paddingRight')+' '+$this.css('paddingBottom')+' '+$this.css('paddingLeft');
this.originalSidePaddingTotal=(parseInt($this.css('paddingLeft'))||0)+(parseInt($this.css('paddingRight'))||0);
var paneWidth=$this.innerWidth();
var paneHeight=$this.innerHeight();
var trackHeight=paneHeight;
$this.wrap(jQuery('<div>').attr({'className':'jScrollPaneContainer'}).css({'height':paneHeight+'px','width':paneWidth+'px'}))}var p=this.originalSidePaddingTotal;
$this.css({'height':'auto','width':paneWidth-settings.scrollbarWidth-settings.scrollbarMargin-p+'px','paddingRight':settings.scrollbarMargin+'px'});
var contentHeight=$this.outerHeight();
var percentInView=paneHeight/contentHeight;
if(percentInView<.98){var $container=$this.parent();
$container.append(jQuery('<div>').attr({'className':'jScrollPaneTrack'}).css({'width':settings.scrollbarWidth+'px'}).append(jQuery('<div>').attr({'className':'jScrollPaneDrag'}).css({'width':settings.scrollbarWidth+'px'}).append(jQuery('<div>').attr({'className':'jScrollPaneDragTop'}).css({'width':settings.scrollbarWidth+'px'}),jQuery('<div>').attr({'className':'jScrollPaneDragBottom'}).css({'width':settings.scrollbarWidth+'px'}))));
var $track=jQuery('>.jScrollPaneTrack',$container);
var $drag=jQuery('>.jScrollPaneTrack .jScrollPaneDrag',$container);
if(settings.showArrows){var currentArrowButton;
var currentArrowDirection;
var currentArrowInterval;
var currentArrowInc;
var whileArrowButtonDown=function(){if(currentArrowInc>4||currentArrowInc%4==0){positionDrag(dragPosition+currentArrowDirection*mouseWheelMultiplier)}currentArrowInc++};
var onArrowMouseUp=function(event){jQuery('body').unbind('mouseup',onArrowMouseUp);
currentArrowButton.removeClass('jScrollActiveArrowButton');
clearInterval(currentArrowInterval)};
var onArrowMouseDown=function(){jQuery('body').bind('mouseup',onArrowMouseUp);
currentArrowButton.addClass('jScrollActiveArrowButton');
currentArrowInc=0;
whileArrowButtonDown();
currentArrowInterval=setInterval(whileArrowButtonDown,100)};
$container.append(jQuery('<a>').attr({'href':'javascript:;','className':'jScrollArrowUp'}).css({'width':settings.scrollbarWidth+'px'}).html('Scroll up').bind('mousedown',function(){currentArrowButton=jQuery(this);
currentArrowDirection=-1;
onArrowMouseDown();
this.blur();
return false}),jQuery('<a>').attr({'href':'javascript:;','className':'jScrollArrowDown'}).css({'width':settings.scrollbarWidth+'px'}).html('Scroll down').bind('mousedown',function(){currentArrowButton=jQuery(this);
currentArrowDirection=1;
onArrowMouseDown();
this.blur();
return false}));
if(settings.arrowSize){trackHeight=paneHeight-settings.arrowSize-settings.arrowSize;
$track.css({'height':trackHeight+'px',top:settings.arrowSize+'px'})}else{var topArrowHeight=jQuery('>.jScrollArrowUp',$container).height();
trackHeight=paneHeight-topArrowHeight-jQuery('>.jScrollArrowDown',$container).height();
$track.css({'height':trackHeight+'px',top:topArrowHeight+'px'})}}var $pane=jQuery(this).css({'position':'absolute','overflow':'visible'});
var currentOffset;
var maxY;
var mouseWheelMultiplier;
var dragPosition=0;
var dragMiddle=percentInView*paneHeight/2;
var getPos=function(event,c){var p=c=='X'?'Left':'Top';
return event['page'+c]||(event['client'+c]+(document.documentElement['scroll'+p]||document.body['scroll'+p]))||0};
var ignoreNativeDrag=function(){return false};
var initDrag=function(){ceaseAnimation();
currentOffset=$drag.offset(false);
currentOffset.top-=dragPosition;
maxY=trackHeight-$drag[0].offsetHeight;
mouseWheelMultiplier=2*settings.wheelSpeed*maxY/contentHeight};
var onStartDrag=function(event){initDrag();
dragMiddle=getPos(event,'Y')-dragPosition-currentOffset.top;
jQuery('body').bind('mouseup',onStopDrag).bind('mousemove',updateScroll);
if(jQuery.browser.msie){jQuery('body').bind('dragstart',ignoreNativeDrag).bind('selectstart',ignoreNativeDrag)}return false};
var onStopDrag=function(){jQuery('body').unbind('mouseup',onStopDrag).unbind('mousemove',updateScroll);
dragMiddle=percentInView*paneHeight/2;
if(jQuery.browser.msie){jQuery('body').unbind('dragstart',ignoreNativeDrag).unbind('selectstart',ignoreNativeDrag)}};
var positionDrag=function(destY){destY=destY<0?0:(destY>maxY?maxY:destY);
dragPosition=destY;
$drag.css({'top':destY+'px'});
var p=destY/maxY;
$pane.css({'top':((paneHeight-contentHeight)*p)+'px'})};
var updateScroll=function(e){positionDrag(getPos(e,'Y')-currentOffset.top-dragMiddle)};
var dragH=Math.max(Math.min(percentInView*paneHeight,settings.dragMaxHeight),settings.dragMinHeight);
$drag.css({'height':dragH+'px'}).bind('mousedown',onStartDrag);
var trackScrollInterval;
var trackScrollInc;
var trackScrollMousePos;
var doTrackScroll=function(){if(trackScrollInc>8||trackScrollInc%4==0){positionDrag((dragPosition-((dragPosition-trackScrollMousePos)/2)))}trackScrollInc++};
var onStopTrackClick=function(){clearInterval(trackScrollInterval);
jQuery('body').unbind('mouseup',onStopTrackClick).unbind('mousemove',onTrackMouseMove)};
var onTrackMouseMove=function(event){trackScrollMousePos=getPos(event,'Y')-currentOffset.top-dragMiddle};
var onTrackClick=function(event){initDrag();
onTrackMouseMove(event);
trackScrollInc=0;
jQuery('body').bind('mouseup',onStopTrackClick).bind('mousemove',onTrackMouseMove);
trackScrollInterval=setInterval(doTrackScroll,100);
doTrackScroll()};
$track.bind('mousedown',onTrackClick);
if($container.mousewheel){$container.mousewheel(function(event,delta){initDrag();
ceaseAnimation();
var d=dragPosition;
positionDrag(dragPosition-delta*mouseWheelMultiplier);
var dragOccured=d!=dragPosition;
return!dragOccured},false)}var _animateToPosition;
var _animateToInterval;
function animateToPosition(){var diff=(_animateToPosition-dragPosition)/3;
if(diff>1||diff<-1){positionDrag(dragPosition+diff)}else{positionDrag(_animateToPosition);
ceaseAnimation()}}var ceaseAnimation=function(){if(_animateToInterval){clearInterval(_animateToInterval);
delete _animateToPosition}};
var scrollTo=function(pos){ceaseAnimation();
var destDragPosition=-pos/(paneHeight-contentHeight)*maxY;
if(settings.animateTo){_animateToPosition=destDragPosition;
_animateToInterval=setInterval(animateToPosition,100)}else{positionDrag(destDragPosition)}};
$this[0].scrollTo=scrollTo;
$this[0].scrollBy=function(delta){var currentPos=-parseInt($pane.css('top'))||0;
scrollTo(currentPos+delta)};
initDrag();
jQuery.jScrollPane.active.push($this[0])}else{$this.css({'height':paneHeight+'px','width':paneWidth-this.originalSidePaddingTotal+'px','padding':this.originalPadding})}})};
jQuery(window).bind('unload',function(){var els=jQuery.jScrollPane.active;
for(var i=0;
i<els.length;
i++){els[i].scrollTo=els[i].scrollBy=null}});